in Fluids. 280, 



was melted in the very beginning of the experiments, or 

 while the hot water was actually -pouring into the jar, 

 which operation commonly lasted about one minute ; and 

 the irregularities in the results of the experiments, and 

 particularly of the three first, showed evidently that the 

 quantity of ice melted in that operation was different in 

 different experi-ments. I had indeed foreseen that this 

 would be the case, and n that account it was that I cov- 

 ered the surface of the ice with a circular piece of strong 

 paper, and always took care to pour the water very 

 gently into the jar; but I found that all these precau- 

 tions were not sufficient to prevent very considerable 

 anomalies in the results of the experiments ; and as I 

 found reason to suspect that the motion in the mass of 

 the hat water, which was unavoidably occasioned by re- 

 moving the circular piece of paper which covered the ice, 

 was the principal cause of these inaccuracies, I had re- 

 course to another and a better ^contrivance. 



Having procured a flat, shallow dish, of light wood, 

 half an inch deep, 4^ inches in diameter (or something 

 less than the internal diameter of the jar), and about \ 

 of an inch thick at its bottom, I bored a great number 



* o 



of very small holes through its bottom, which gave it 

 the appearance of a sieve. This perforated wooden dish, 

 having been previously made ice-cold^ was placed on the 

 surface of the ice in the jar, and the hot water being 

 gently poured into the dish through a long wooden tube, 

 as this perforated dish floated and remained constantly 

 at the surface of the water, and as the water passing 

 through such a great number (many hundreds) of small 

 holes was not projected downwards with force, it is evi- 

 dent that by this simple contrivance those violent motions 

 in the mass of water in the jar which before took place 



VOL. I. 19 



